China confirms H5N6, H7N9 infections

Chinese health officials have confirmed the second case of H5N6 avian flu in a week, the World Health Organization (WHO) said today, while also reporting a new case of H7N9 avian flu. The H5N6 infection is the world's sixth.

The new H5N6 case involved a 40-year-old woman in Zhaoqing city in Guangdong province, the same province that reported a case on Dec 29, according to the WHO report. The woman became sick on Dec 22, was hospitalized on Dec 28, and is in critical condition. The previous patient was in Shenzhen, about 100 miles southeast of Zhaoqing.

The WHO also noted that last week's patient, a 26-year-old woman, fell ill on Dec 24 and was hospitalized on Dec 27. As noted by officials last week, she is in critical condition. The first H5N6 case, also in China, was confirmed in May 2014.Jan 4 WHO update

The H7N9 case involves a 59-year-old man undergoing treatment in Shanghai, according to a Jan 1 news release from Hong Kong's Centre for Health Protection (CHP). The agency provided no further details, such as possible poultry exposure.

CDC data show steady rise in flu activity

Flu activity in the United States appears to be ramping up a bit, with several key indicators showing increased activity and the 2009 H1N1 strain continuing its recent surge past H3N2, according to an update today from the Centers for Disease Control and Prevention (CDC).

The percentage of visits for influenza-like illness (ILI) rose to 2.6% for the week ending Dec 26, which is above the national baseline of 2.1% and up from 2.2% the week before. Also, 6 of the 10 CDC regions registered above region-specific baseline levels, up from 4 the previous week.

Puerto Rico, New Jersey, and Connecticut reported high ILI activity for the week, with Arizona, Georgia, and Virginia experiencing moderate ILI levels. Last week just South Carolina reported high activity, while Puerto Rico, New Jersey, and Texas noted moderate ILI levels.

North Carolina and Guam reported widespread influenza activity last week, versus no states or territories the week before. Five states reported regional activity, and 12 noted local flu activity. The week before, 5 states also reported regional activity, while 14 had local activity.

Deaths from pneumonia and flu were down a bit week to week, from 6.3% to 6.0%, and well below the epidemic threshold of 7.2% for the week. No new flu-related deaths in kids were reported, keeping that number at four for the season.

Of the 38 influenza A viruses tested during the week, 32 (84%) were 2009 H1N1 and 6 (16%) were H3N2, a similar ratio to the week before. Overall, 56% of positive respiratory samples were influenza A and 44% were influenza B.

After recent cases, PAHO cautions nations about yellow fever

The Pan American Health Organization (PAHO) recently cautioned countries in the region about yellow fever in light of increased reports and the possibly confounding presence of El Nino weather patterns.

Peru had 23 probable or confirmed cases of yellow fever in 2015, mostly in Loreto (8 cases), Junin (5), and San Martin (5) regions, PAHO said in a Dec 31 epidemiologic alert. This is up from 15 probable or confirmed cases in 2014.

From July 2014 to June 2015, Brazil reported 7 human and 11 non-human primate cases. Of the 7 infected people, 4 died. None had received vaccinations. All cases were in the east-central part of the country.

In Bolivia, no human cases of yellow fever have occurred, but the virus killed an unspecified number of non-human primates in December, the agency noted.

As for El Nino, studies have linked a periodic increase of mosquito-transmitted diseases such as malaria and dengue fever to the weather pattern. For example, a US study in 1999 determined that in the all but two of the US yellow fever epidemics from 1793 through 1905 were associated with El Nino. Because the phenomenon creates a wetter and more humid environment, infected mosquitos might be able to spread the virus better.

PAHO recommends that countries improve their ability to detect and confirm yellow fever, keep health professionals updated, and ensure high-risk populations have been effectively vaccinated. Ten days after receiving yellow fever vaccination, 80% to 100% of people have effective immunity against the disease, the agency noted.Dec 31 PAHO alertJanuary 1999 El Nino study